大般涅槃經義記 2.207

2.207

迦葉初先執喻同法難佛無常；下佛答之，簡法異喻，明佛是常，先呵難詞，下為辯釋。釋中，初明法身體常，「一切法」下明佛報常。前中，初言「如世間器，如來世尊無上法器」，約喻顯法。如來法身本為妄依，容受妄想，故名法器，是故前以燈爐為譬。「而器無常，非如來也」，辯法異喻，異故是常，明報常中一切法中涅槃法常，舉本顯末，所謂性淨。「涅槃法常，如來體之名為常」者，名為報常。

Kāśyapa first clung to the analogy as being identical to the Dharma to challenge the Buddha regarding impermanence; below, the Buddha answers him, distinguishing the Dharma as differing from the analogy and explaining that the Buddha is permanent. First he rebukes the words of the challenge, and below he explains it. In the explanation: first, he explains that the essence of the dharmakāya is permanent; from "all dharmas" onward, he explains that the Buddha's retribution is permanent. In the former part, it first says: "Just as in the world there are vessels, the Tathāgata, the World-Honoured One, is an unsurpassed Dharma vessel," using the analogy to reveal the Dharma. The Tathāgata's dharmakāya is originally the basis of delusion and holds false conceptualizations, hence it is called a Dharma vessel; therefore, previously he used the lamp bowl as a metaphor. "Yet the vessel is impermanent, but not the Tathāgata" distinguishes the Dharma as differing from the analogy; because it differs, it is permanent. In explaining that the retribution is permanent: among all dharmas, the dharma of nirvāṇa is permanent; he adduces the root to reveal the branch, namely the naturally pure. "The dharma of nirvāṇa is permanent, and the Tathāgata embodies it and is called permanent" refers to the permanence of retribution.